refactor(cli): target ruff 310 (#32985)

Use union types for optional parameters

libs/cli/langchain_cli/namespaces/app.py

@@ -5,7 +5,7 @@ import subprocess
 import sys
 import warnings
 from pathlib import Path
-from typing import Annotated, Optional
+from typing import Annotated
 
 import typer
 import uvicorn
@@ -35,18 +35,18 @@ app_cli = typer.Typer(no_args_is_help=True, add_completion=False)
 @app_cli.command()
 def new(
     name: Annotated[
-        Optional[str],
+        str | None,
         typer.Argument(
             help="The name of the folder to create",
         ),
     ] = None,
     *,
     package: Annotated[
-        Optional[list[str]],
+        list[str] | None,
         typer.Option(help="Packages to seed the project with"),
     ] = None,
     pip: Annotated[
-        Optional[bool],
+        bool | None,
         typer.Option(
             "--pip/--no-pip",
             help="Pip install the template(s) as editable dependencies",
@@ -127,24 +127,24 @@ def new(
 @app_cli.command()
 def add(
     dependencies: Annotated[
-        Optional[list[str]],
+        list[str] | None,
         typer.Argument(help="The dependency to add"),
     ] = None,
     *,
     api_path: Annotated[
-        Optional[list[str]],
+        list[str] | None,
         typer.Option(help="API paths to add"),
     ] = None,
     project_dir: Annotated[
-        Optional[Path],
+        Path | None,
         typer.Option(help="The project directory"),
     ] = None,
     repo: Annotated[
-        Optional[list[str]],
+        list[str] | None,
         typer.Option(help="Install templates from a specific github repo instead"),
     ] = None,
     branch: Annotated[
-        Optional[list[str]],
+        list[str] | None,
         typer.Option(help="Install templates from a specific branch"),
     ] = None,
     pip: Annotated[
@@ -186,7 +186,7 @@ def add(
     )
 
     # group by repo/ref
-    grouped: dict[tuple[str, Optional[str]], list[DependencySource]] = {}
+    grouped: dict[tuple[str, str | None], list[DependencySource]] = {}
     for dep in parsed_deps:
         key_tup = (dep["git"], dep["ref"])
         lst = grouped.get(key_tup, [])
@@ -305,7 +305,7 @@ def remove(
     api_paths: Annotated[list[str], typer.Argument(help="The API paths to remove")],
     *,
     project_dir: Annotated[
-        Optional[Path],
+        Path | None,
         typer.Option(help="The project directory"),
     ] = None,
 ) -> None:
@@ -344,15 +344,15 @@ def remove(
 def serve(
     *,
     port: Annotated[
-        Optional[int],
+        int | None,
         typer.Option(help="The port to run the server on"),
     ] = None,
     host: Annotated[
-        Optional[str],
+        str | None,
         typer.Option(help="The host to run the server on"),
     ] = None,
     app: Annotated[
-        Optional[str],
+        str | None,
         typer.Option(help="The app to run, e.g. `app.server:app`"),
     ] = None,
 ) -> None: